Sequence valve

ABSTRACT

A valve which alternately pressurizes two outlet ports from a single inlet port in response to successive signal pulses at the inlet port. The valve comprises a spool with end chambers and a central spring-controlled shuttle. A plurality of such valves may be stacked to form a series air index, so that the outlet ports will be pressurized in sequence. By altering the construction of one or more valves so that their end chambers can be pressurized only from an external source, a binary counter may be formed from stacked valves, whereby the input signals will pressurize the outlet ports non-serially to pressurize a particular outlet port after a fixed member of input signals.

United States Patent Bitonti [is] 3,654,958 51 Apr.1l,1972

[54] SEQUENCE VALVE [72] Inventor: Paul A. Bitonti, Dearbom Heights, Mich.

[73] Assignee: Ross Operating Valve Company, Detroit,

Mich.

221 Filed: Dec.18,1970 [21] Appl.No.: 99,416

[52] U.S. Cl ..l37/596.l4, 137/624.27 [51] lnt.Cl ..Fl6kl1/07,Fl6k 11/10 [58] Field of Search ..137/596.14, 596.15, 624.27,

[56] References Cited UNITED STATES PATENTS 3,011,519 12/1961 Brinkelet a1. ..l37/624.27 3,131,722 5/1964 Abbott et al. ..l37/625.66X

3,459,224 8/1969 Weber ..137/625.63

Primary Examiner-Henry T. Klinksiek Attorneyl-lamess, Dickey & Pierce [57] ABSTRACT A valve which alternately pressurizes two outlet ports from a single inlet port in response to successive signal pulses at the inlet port. The valve comprises a spool with end chambers and a central spring-controlled shuttle. A plurality of such valves may be stacked to form a series air index, so that the outlet ports will be pressurized in sequence. By altering the construction of one or more valves so that their end chambers can be pressurized only from an external source, a binary counter may be formed from stacked valves, whereby the input signals will pressurize the outlet ports non-serially to pressurize a particular outlet port after a fixed member of input signals.

7 Claims, 7 Drawing Figures PATENTEDAPR 11 I972 3,654,958

' sum 3 or 4 INVENTOR.

fdzl ACE/7 0772 11 SEQUENCE VALVE BACKGROUND OF THE INVENTION l. Field of the Invention The invention relates to fluid-operated sequence valves used to control functions in response to a specified number of input pressure pulses.

2. Description of the Prior Art A number of indexing fluid control devices have been developed, such as that shown in US. Pat. No. 3,459,224 issued to Alfred R. Weber on Aug. 5, 1969. This prior construction is for the purpose of successively pressurizing and exhausting a single outlet connection in response to successive signal pulses. The prior unit has a constantly pressurized supply port which is separate from the signal port, and this supply port remains connected to the outlet port during both application and removal of the first signal pulse. The outlet port is exhausted during both application and removal of the second signal pulse.

In using this prior art device for indexing purposes, the count is limited to 2". That is, stacking of the prior units would achieve pressurizing of a particular outlet port only after 2" input signals had been applied and removed. Furthermore, the prior unit is relatively complicated in its construction, relying on differential seal areas to hold the valve in its alternate positions.

SUMMARY OF THE INVENTION The present invention affords the ability to pressurize a particular outlet port after any fixed number of input signals have been applied and removed, regardless of whether that number is 2". In other words, the present invention affords unlimited count ability.

The unit has a single inlet port which acts both as a signal and a supply port, and two outlet ports. A spool is shiftable between first and second positions and has two end chambers which, in one embodiment, are alternately connectable to the inlet port. A central shuttle valve is shiftable between two positions in response to successive inlet pulses.

When both end chambers are connectable to the inlet port, application of a first inlet signal will pressurize the first outlet port and exhaust the second outlet port. When the first inlet signal is removed, the first outlet port will be exhausted, the second also remaining exhausted. Application of the second signal will pressurize the second outlet port, the first remaining exhausted. Removal of the second signal will again exhaust both outlet ports. The single unit thus performs a switching actron.

Stacked units may function as a series air index or as a binary counter. As a series air index, successively applied pressure signals will pressurize the available outlet ports serially and then repeat. For example, a three unit stack will give four count ability. When used in this manner, the invention will result in a substantial savings over presently available methods in the number of valves and piping required.

As a binary counter, stacked units will pressurize a particular outlet port only after a fixed number of input signals had been applied and removed. For example a four unit stack could be arranged to pressurize an outlet port after each 12th input signal. To accomplish this type of result, end chambers in certain units would not be connectable to the inlet ports of these units but would be pressurizable from an outlet port of another unit. The input signals would thus pressurize the outlet ports non-serially to achieve the desired count.

The units are of relatively simple construction and eliminate the need for a latching means or differential seal areas to hold the spools in their end positions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view in elevation of one of the units shown with both end chambers connectable to the inlet port;

FIG. 2 is a view similar to FIG. 1 but showing the unit with a first pressure signal applied to the inlet port;

FIG. 3 is a view similar to FIGS. 1 and 2 but showing the unit after the first inlet signal has been removed;

FIG. 4 is a view similar to FIG. 3 but showing the unit after the second inlet signal has been applied;

FIG. 5 is a diagrammatic view of a second embodiment of the invention comprising three stacked units used as a series air index;

FIG. 6 is a partially diagrammatic view of a second embodiment of the invention in which four stacked units perform the function of a binary counter; and

FIG. 7 is a chart showing the operation of the embodiment of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to the single unit shown in FIG. 1, this unit is generally indicated at 11 and comprises a housing 12 having an inlet port 13, first and second outlet ports 14 and 15 spaced outwardly from port 13 and on the opposite side of body 12, and a pair of plugged (non-operational) ports 16 and 17.

Body 12 has a bore 18 within which is disposed a spool generally indicated at 19. Spool 19 has a central portion 21 of reduced diameter forming a chamber connected with inlet port 13-, and left and right hand portions 22 and 23 of reduced diameter forming chambers connected with outlet ports 14 and 15 respectively. Seals 24 and 25 separate the central reduced portion of the spool from the left and right hand portions respectively. End chambers 26 and 27 are formed in bore 18 by seals 28 and 29 respectively on spool 19 and by seals 31 and 32 carried by end caps 33 and 34. These end caps are retained against outward movement by rings 35 and 36 against which they are urged by springs 37 and 38 respectively within hollow extensions 39 and 41 of the end caps. Manual pressure on the end caps will shift spool 19 between the left and right hand positions shown in FIG. 1 and 2 respectively.

A pair of hollow inserts 42 and 43 are disposed within the left and right hand ends respectively of a bore 44 within spool 19. The inserts are held in place by retaining rings 45 and 46 and shoulders 47 and 48. Radial passages 49 and 51 are provided in inserts 42 and 43 respectively and connect the interiors of the inserts with radial passages 52 and 53 in spool 19. Passages 52 are disposed between seals 24 and 28 whereas passages 53 are between seals 25 and 29. Therefore, the interior passage 54 of insert 42 will always be connected with outlet port 14 whereas the interior passage 55 of insert 43 is constantly connected to outlet port 15. These two interior passages are connectable to the central inlet chamber 56 of spool 19, and a shuttle 57 is slidably mounted in this chamber and is engageable with either one insert or the other to close off its corresponding passage. Chamber 56 is constantly connected to inlet port 13 by radial ports 58 in spool 19. Shuttle 57 is engaged on its opposite sides by springs 37 and 38, these springs being of the same strength so that they will tend to hold shuttle 57 in its midposition. When spool 19 is in its left hand position as shown in FIG. 1, insert 43 will hold shuttle 57 slightly to the left of its center position so that spring 37 will firmly urge the shuttle against this insert. A seal 59 is carried by shuttle 57 and is engageable with insert 43 to separate chamber 56 from passage 55. Similarly, a seal 61 carried by shuttle 57 is engageable with insert 42 to separate chamber 56 from passage 54.

In order to prevent pressurized fluid from being inadvertently trapped in outlet ports 14 or 15, restricted bleed passages 62 and 63 are provided for these ports respectively. These passages are formed in body 12 and lead from the chambers formed by reduced sections 22 and 23 respectively of spool 19.

The means for pressurizing end chambers 26 and 27 in the embodiment of FIGS. 1 to 4 comprises radial passages 64 and 65 in extensions 39 and 41 respectively of the end caps-These passages are connected with interior passages 54 and 55 of inserts 42 and 43. As will be later seen with respect to the embodiment of FIGS. 6 and 7, a passage 64 or 65 may be omitted in any particular unit 11 of a stack of such units. The consequence of this would be that the corresponding end chamber would not be pressurized from central chamber 56, being pressurized instead by an external connection leading from the outlet port of another unit in the stack.

The dimensions of passages 64 and 65 are such that spool 19 will not be slammed against either end cap 33 or 34 when the end chambers are being pressurized.

In operation, assuming an initial condition is shown in FIG. 1, with spool 19 in its left hand position and inlet port 13 exhausted, shuttle 57 will be held against seat 66 at the end of insert 43 by spring 37. Pressurization of inlet port 13, as the first signal, will cause fluid to flow through chamber 67 around reduced portion 21 of spool 19, through passages 58, and into central chamber 56 to the left of shuttle 57. The fluid will then flow into central passage 54 of insert 42 and through passages 49 and 52 into a chamber 68 surrounding reduced portion 22 of spool 19. From there the fluid will flow into outlet port 14, pressurizing this port. The fluid pressure will hold shuttle 57 against seat 66 so that no pressurized fluid may flow to outlet port 15. At the same time any remaining pressurized fluid in outlet port 15 will pass through chamber 69 around reduced portion 23 of the spool and through exhaust port 63 which is provided with a filter 71.

Pressurized fluid will also pass through passage 64 into end chamber 26 and shift spool 19 to the right as shown in FIG. 2. Because of the pressure in chamber 56, shuttle 57 will still remain in its position with seal 59 engaging seat 66.

Upon removal of the pressure at inlet port 13, pressurized fluid will flow from outlet port 14 through chamber 68, passages 52 and 49, passage 54, chamber 56, passages 58 and chamber 67 to port 13. The reduction of pressure in chamber 56 will permit spring 38 to shift shuttle 57 to the left as shown in FIG. 3 so that seal 61 engages seat 72 at the end of insert 42. At this point, therefore, both outlet ports 14 and 15 will be exhausted, with any remaining pressure in outlet port 14 leaving through exhaust port 62.

Upon the next application of pressure at inlet port 13, fluid will pressurize chamber 56 again and will travel through passages 55, 51, 53 and chamber 69 to port 15, pressurizing this outlet port. The pressurized fluid will also travel through passage 65 to end chamber 27, shifting spool 19 to its left hand position as shown in FIG. 4. The pressure in chamber 56 will hold shuttle 57 with its seal 61 against seat 72 of insert 42. Outlet port 14 will remain exhausted.

The next exhaustion of inlet port 13 will result in outlet port 15 being exhausted through chamber 69, passages 53, 51 and 55, and chambers 56 and 67. Any remaining pressure in outlet port 15 will be exhausted through exhaust port 63. Shuttle 57 will be shifted by spring 37 to its right hand position and the parts will therefore assume the positions shown in FIG. 1, ready for recycling.

FIG. shows in schematic fashion a second embodiment of the invention in which three units 11a, 11b and 110 are stacked to sequentially control the extension and retraction of three air-operated clamps A, B and C. A manually operable valve 101 is connected with inlet port 13a of unit 11a and the outlet 14a is connected to one side of a control valve 102 for clamps A. Outlet port a is connected to the inlet port 13b of unit 11b. Outlet port 14b of unit 11b is connected to valve 103 of clamps B, and outlet port 15b to inlet port 130 of unit 110. Outlet port 140 is connected with a control valve 104 for clamps C and outlet port 150 to the opposite sides of all three valves 102, 103 and 104.

In operation, the individual units 11a, 11b and 110 will all operate as described above for unit 11. As a result, the first actuation of valve 101 will cause clamps A to extend. The second reciprocation of the manual valve will cause clamps B to extend and the third actuation will extend clamps C. The fourth actuation will cause all clamps to retract, thereby completing the sequence.

FIGS. 6 and 7 show in partially diagrammatic fashion a binary counter made up of four stacked units 11, these units being designated as I, II, III and IV respectively. The purpose of this arrangement is to pressurize and exhaust a particular outlet port 15 of unit IV at the twelfth application and removal of signal pressure. The inlet port 13 of unit I is the signal port and outlet port 14 of this unit is plugged, as are the outlet ports 14 of the other three units. The outlet port 15 of unit I is connected to inlet port 13 of unit II, the outlet port 15 of unit II to the inlet port 13 of unit III and the outlet port 15 of unit III to the inlet port 13 of unit IV.

All four units are provided with passages 64 and 65 with the exception that passage 65 is missing from unit I. Instead, end chamber 27 of unit I is pressurized by a conduit 201 leading from end chamber 27 of unit II. Because of this, the stack will perform the following operation as shown in FIG. 7:

Starting with an initial position as shown in FIG. 6, signal port 13 of unit I will be connected to plugged outlet port 14 of unit I. The first application and removal of signal pressure will shift the spool of unit I to the right, with no action at the other units. This will cause the signal port to be connected to plugged outlet port 14 of unit II.

Upon application of the next signal pulse (Signal No. 2) unit I will not shift back to the left hand position because of the fact that no passage 65 exists in unit I. However, unit I] will shift to the right hand position, units III and IV remaining stationary. At the end of the second signal pulse, the signal port will be connected to plugged outlet port 14 of unit III which is plugged.

Application of the third signal pulse will cause pressure to be applied to end chamber 27 of unit Il, shifting unit [I to the left. This pressure will also be transmitted through conduit 201 to end chamber 27 of unit I, shifting unit I to the left. Unit III will be shifted to the right. However, after the third signal pulse, the signal port will only be connected to plugged outlet port 14 of unit I.

The fourth signal pulse will again shift unit I to the right with no action at the other units, as a result of which the signal port will be connected to plugged outlet port 14 of unit II.

A fifth signal pulse will cause unit II to shift to the right, the other units remaining stationary. At the end of the fifth pulse the signal port will be connected to plugged outlet port 14 of unit IV.

The sixth signal pulse will again return units I, II and III to their left hand positions and will shift unit IV to its right hand position. At the end of this pulse the signal port will again be connected to plugged outlet port 14 of unit I.

The seventh, eighth, ninth and tenth signal pulses will be repeats of the first, second, third and fourth, so that at the end of the tenth signal pulse units I, III and IV will be shifted to the right and unit II will be in its left hand position. At the eleventh signal pulse, unit II will shift to its right hand position and at the end of the eleventh pulse the signal port will be connected to outlet port 15 of unit IV, which is the port being controlled.

Therefore, upon application of the twelfth signal pulse pressurized fluid will flow from signal port 13 of unit I to outlet port 15 ofunit IV. All units I through IV will shift to the left, but the pressure will remain at the controlled outlet port until pressure is removed from the signal port, at which time all the parts will be in their starting position.

What is claimed is:

l. A sequence valve comprising a body having an inlet port and first and second outlet ports, means responsive to a first application of fluid pressure at said inlet port for pressurizing said first outlet port, means responsive to removal of said first pressure application at said inlet port for exhausting said first outlet port, means responsive to a second pressure application at said inlet port for pressurizing said second outlet port, means responsive to removal of said second pressure application at the inlet port for exhausting said second outlet port, and means responsive to a third pressure application at said inlet port for again pressurizing said first outlet port, whereby said first and second outlet ports will be alternately pressurized and exhausted by repeated applications and removals of pressure at the inlet port.

2. The combination according to claim 1, further provided with means for insuring exhaust of a non-pressurized outlet port comprising restrictive exhaust passages in said body.

3. In a sequencing valve, a valve body, a spool shiftable in said body and forming therewith an inlet chamber and a pair of spaced outlet chambers, an inlet port connected to said inlet chamber, first and second outlet ports connected to said outlet chambers, a central chamber within said spool connected to said inlet chamber, a shuttle in said central chamber, springs urging said shuttle toward a central position, a pair of chambers at opposite ends of said spool, the spool being movable between left and right hand positions in response to pressure in said end chambers, and first and second passages in said spool connecting said central chamber to said first and second outlet chambers respectively, whereby a first application of pressure at the inlet port with the spool in its left hand position will pressurize said first outlet port and cause said shuttle to seal said second passage from said central chamber, reduction of pressure at said inlet port after said first outlet port has been pressurized will exhaust said first outlet port, a second application of pressure at the inlet port with the spool in its right hand position will pressurize said second outlet port and cause said shuttle to seal said first passage from said central chamber, and reduction of pressure at the inlet port after said second outlet port has been pressurized will exhaust said second outlet port.

4. The combination according to claim 3, further provided with a passage between said first spool passage and the left hand end chamber whereby said first pressure application will cause shifting of said spool from its left to its right hand position.

5. The combination according to claim 4, further provided with a passage between said second spool passage and the other end chamber, whereby the second application of pressure at the inlet port will return said spool to its left hand position.

6. The combination according to claim 5, further provided with restricted exhaust passages in said body for insuring exhaustion of said outlet ports.

7. The combination according to claim 4, further provided with a second sequence valve like said first valve, the second outlet port of said first sequence valve being connected to the inlet port of said second sequence valve, said second sequence valve having passages connecting the first and second spool passages thereof with their corresponding end chambers, one of the end chambers of said second sequence valve being connected to the right hand end chamber of said first sequence valve whereby the spool of said first sequence valve will be returned to its left hand position in response to application of pressure in said one end chamber of the second sequence valve. 

1. A sequence valve comprising a body having an inlet port and first and second outlet ports, means responsive to a first application of fluid pressure at said inlet port for pressurizing said first outlet port, means responsive to removal of said first pressure application at said inlet port for exhausting said first outlet port, means responsive to a second pressure application at said inlet port for pressurizing said second outlet port, means responsive to removal of said second pressure application at the inlet port for exhausting said second outlet port, and means responsive to a third pressure application at said inlet port for again pressurizing said first outlet port, whereby said first and second outlet ports will be alternately pressurized and exhausted by repeated applications and removals of pressure at the inlet port.
 2. The combination according to claim 1, further provided with means for insuring exhaust of a non-pressurized outlet port comprising restrictive exhaust passages in said body.
 3. In a sequencing valve, a valve body, a spool shiftable in said body and forming therewith an inlet chamber and a pair of spaced outlet chambers, an inlet port connected to said inlet chamber, first and second outlet ports connected to said outlet chambers, a central chamber within said spool connected to said inlet chamber, a shuttle in said central chamber, springs urging said shuttle toward a central position, a pair of chambers at opposite ends of said spool, the spool being movable between left and right hand positions in response to pressure in said end chambers, and first and second passages in said spool connecting said central chamber to said first and second outlet chambers respectively, whereby a first application of pressure at the inlet port with the spool in its left hand position will pressurize said first outlet port and cause said shuttle to seal said second passage from said central chamber, reduction of pressure at said inlet port after said first outlet port has been pressurized will exhaust said first outlet port, a second application of pressure at the inlet port with the spool in its right hand position will pressurize said second outlet port and cause said shuttle to seal said first passage from said central chamber, and reduction of pressure at the inlet port after said second outlet port has been pressurized will exhaust said second outlet port.
 4. The combination according to claim 3, further provided with a passage between said first spool passage and the left hand end chamber whereby said first pressure application will cause shifting of said spool from its left to its right hand position.
 5. The combination according to claim 4, further provided with a passage between said second spool passage and the other end chamber, whereby the second application of pressure at the inlet port will return said spool to its left hand position.
 6. The combination according to claim 5, further provided with restricted exhaust passages in said body for insuring exhaustion of said outlet ports.
 7. The combination according to claim 4, further provided with a second sequence valve like said first valve, the second outlet port of said first sequence valve being connected to the inlet port of said second sequence valve, said second sequence valve having passages connecting the first and second spool passages thereof with their corresponding end chambers, one of the end chambers of said second sequence valve being connected to the right hand end chamber of said first sequence valve whereby the spool of said first sequence valve will be returned to its left hand position in response to application of pressure in said one end chamber of the second sequence valve. 